Field of the Invention
The present invention relates to non-contact power supply systems.
Description of the Related Art
Non-contact power supply systems including a power supply apparatus, having a primary coil for outputting power in a non-contact manner without physically connecting to a connector as an antenna, and a power receiving apparatus, having a secondary coil for receiving power supplied from the power supply apparatus in a non-contact manner as an antenna, are known.
A non-contact power supply system is implemented by the power supply apparatus and the power receiving apparatus exchanging control information pertaining to the power to be supplied/received. Methods have been proposed in which non-contact communication such as NFC is used to exchange the control information. Other methods, in which the exchange is carried out using communication systems having broader communication ranges, have been proposed as well. Rezence (registered trademark), for example, specifies exchanging power supply control information using Bluetooth (registered trademark) Low Energy (BLE). With such a method, however, the broad communication range means that communication may also be carried out with a partner that is not the partner to which power is to be supplied. In this case, the information of the partner to which power is actually to be supplied is not obtained, and thus correct power supply control cannot be carried out, which leads to problems such as overcharging.
To prevent such problems, Japanese Patent Laid-Open No. 2015-180177 proposes a technique for determining whether or not a communication-connected power receiving apparatus is a target for power supply in accordance with a state of communication with the power receiving apparatus when a power supply apparatus changes a power supply state. This makes it possible to confirm whether or not a connection for communication used in power supply control is successfully established with the power receiving apparatus to which the power supply apparatus is to supply power.
However, according to Japanese Patent Laid-Open No. 2015-180177, it is necessary to first carry out a process for supplying power in order to determine whether or not the power receiving apparatus is the target of the power supply. It is therefore possible that the process for supplying power will result in excessive power being supplied, even if only temporarily.